There are a variety of ironing appliances with external reservoirs in the prior art. Irons with external reservoir units are advantageous in that they provide sufficient steam in terms of both quantity and pressure. A common problem with ironing appliances is the inadequacy of steam in terms of stability and availability in the course of ironing as well as pressure of the same. To overcome this, a common approach is to employ an external steam production unit which is pressurized independently as in industrial ironing appliances. Potential drawback of an ironing appliance with such an external steam generator is that the steam reservoir usually takes up to 5 to 6 times more time than the sole plate to be heated up to an adequate level. Another drawback is the necessity to wait until the reservoir cools down prior to refilling the same. Further, it is known that such reservoirs are bulky and are not suitable for home use.
The present invention employs an external water reservoir to produce steady steam in desired quantities such that it does not require pressurization in the external reservoir for the steam production as the steam is not produced within the reservoir.
The present invention proposes an improved system in which water is first conveyed to an upper soleplate from which it is distributed by a plurality of locations to the lower soleplate, during which distribution conversion into steam phase occurs before contacting the lower soleplate. The steam therefore produced and conveyed to the lower soleplate is independent of the temperature of the lower soleplate or heat accumulated therein.
FR 2853671 also suggests an ironing appliance having an external water reservoir from which water is pumped to an evaporation chamber within the ironing appliance. This approach involves storage of vapor in a pressurized state and conveyance to the soleplate thereof as much as needed. The present invention on the other hand provides the simple effect that steam is not stored or is not stayed for pressurization and is produced directly before reaching the soleplate by means of an additional inner plate. The present invention therefore suggests a far more efficient steam production system as only a desired amount of water is conveyed from the external water reservoir to be directly transformed into steam and consumed without being stored or pressurized to a certain extent. Production of steam is triggered as much as the users demands and without consuming the heat accumulated in the sole plate, hence in the absence of adverse effects to the temperature stability of the sole plate. The external reservoir can be refilled during ironing since it is not pressurized. Further it is not required that the internal steam chamber is regularly monitored to restore diminished water. Due to the fact that an ironing appliance having an external reservoir which can be refilled during ironing requires an additional reservoir with a pump for conveying water to steam generator is the most prominent disadvantage in terms of heightening end user price of the product. The present invention overcomes all the above drawbacks with an iron refillable during ironing with an economically reasonable price.
A prominent prior art reference to the subject matter of claim 1 is disclosed in U.S. Pat. No. 3,263,350. Said document discloses an ironing apparatus comprising a soleplate for ironing a cloth item, a water reservoir for supplying water to be transformed into steam and a heatable inner plate for transforming water conveyed from said external water reservoir into steam.